Cathode Bypass Cap = No Effect

Just for the heck of it, I tried adding a cathode resistor Bypass cap around the 200ohm 10watt cathode resistor used for the two 6V6 tubes in this push pull circuit, and it doesn't seem to do a thing, not at 22uf or 100uf. Doesn't matter either way in the least, no addition to gain or Bass...

There's a couple of things that may influence that behavior. First, the field coil is in series ahead of the plate supply and it's working to maintain a constant current to some degree. Second, even with the push-pull stage, a reasonably warm-biased AB stage will see both tubes conducting for a good bit of the excursion so that the sum of the cathode currents into the cathode resistor stays fairly consistent. Combine those two and the dV/dt across the cathode resistor gets pretty small. That would be my guess, anyway.